Re: SECONDS=0 does not reset SECONDS, or I'm missing something

[dan braun]

Andreas,

I have found that many times operations take much less than a second to
complete.
Therefore a single second may not be enough resolution for the task.

I sometimes use the following;
#nano seconds
# date +%N
688264274

#epoch seconds
# date +%s
1591274861

# sleep 500 milliseconds
# sleep 0.500

Cheers,
Dan
--
Dan Braun (dan @ tekvax . com )
Broadcast Engineering
Burlington, Ontario, Canada


On Thu, 4 Jun 2020 at 09:03, Andreas Kusalananda Kähäri <
andreas.kahari@abc.se> wrote:

> On Thu, Jun 04, 2020 at 03:00:40PM +0200, Kusalananda Kähäri wrote:
> > On Thu, Jun 04, 2020 at 08:48:34AM -0400, Steve Amerige wrote:
> > > On 6/4/2020 6:14 AM, Andreas Kusalananda Kähäri wrote:
> > > >   #!/usr/local/bin/bash -x
> > > >
> > > >   for name do
> > > >           SECONDS=0
> > > >           rm -r -f "$name"
> > > >           [[ SECONDS -gt 0 ]] && sleep "$SECONDS"
> > > >   done
> > > >
> > > > What I noticed was that the script would go to sleep for a second
> > > > every second, even if the deletion of directories was quick.  This
> > > > indicates that SECONDS=0 didn't properly reset the SECONDS timer.
> > >
> > > Note that your script doesn't have a semicolon after "for name":
> > >
> > > for name; do
> > > ...
> > > done
> >
> > That's because it doesn't need one.
> >
> > >From the manual:
> >
> >       for name [ [ in [ word ... ] ] ; ] do list ; done
> >
> > That is, "for name in do list; done" is valid.
>
> Sorry, I meant "for name do list; done" above, which is what I have in
> my code.
>
>
> --
> Andreas (Kusalananda) Kähäri
> SciLifeLab, NBIS, ICM
> Uppsala University, Sweden
>
> .
>
>